Radio receiving apparatus



G. O. WILKINSON RADIO RECEIVING APPARATUS June 2 1925 1,539,889

Filed Jan. 19. 1923 INVENTOR )1 TTORNEY.

Patented Junes2, 1925.

GORDON O. WILKINSON, OF ARDMORE, PENNSYLVANIA;

RADIO nncnrvme APPARATUS.

Application filed January 19, 1923. Serial No. 613,587.

To all whom it may concern:

, Be it known that I, GORDON O. WILKIN- soN, a citizen of the United States, and a resident of Ardmore, in the county of Montgomery and State of Pennsylvania, have invented an Improvement in Radio Receiving Apparatus, of which the following is a specification.

My invention relates to radio receiving apparatus, and it has for its general object toprovide novel means whereby amateursand others desiring to construct and hookup radio receiving apparatus may do so with a minimum amount of difliculty and at the same time secure a maximum efiiciency of reception.

A further objectof the invention is to provide a novel and simplified construction of unit having a minimum number of contr ols which shall-have the capacity for efficiently receiving and detecting waves generated from a long distance. f

A further object of the invention is to provide a combination of inductances with means whereby the same may be connected or booked in the system in many different combinations in a manner to effect great selectivity; and other objects also are to effect elimination of distributed capacity as well also as the effects of body capacity.

A further" object of the invention is to provide an improved construction of means for supporting and controlling the position of the rotor with respect to the stator coils of the apparatus. e

Withoutundertaking at this, time to set forth all of the variousv objects and advantages of my invention I shall now proceed to' a detailed description of the same 0 wherein other objects and advantages thereof will be set forth or will be apparent from such description.

In order that the invention may be more readily understood reference may be had to the accompanying drawing, in which I have illustrated one form. of embodiment of the .invention'and have shown a few circuits indicating the manner in which the device of the invention may be connected in different circuit systems. However, it will be under stood. thatchanges in the details of construction may be made within the scope of the claim without departing from my invention.

as fiber, which in turn is supported upon plurality of strands.

In the drawing:

Fig. 1 is a view partly in longitudinal section and partly in side elevation of a device or. apparat'usiembodying my invention;

Fig. 2 is a transverse sectional view taken on the line 22 of Fig. 1;

Fig. 3 is a view showing a fragmentary portion of the device or apparatus taken on the line 33 of Fig. 1; and

Figs. 4 5 and 6 are views showing an' arrangement and connection of receivingapparatus indicating the manner in which my invention is adapted to be employed.

Before proceeding with the detailed description of the drawing as above briefly described I desire to point out that I have made no effort to indicate all the various arrangements of systems of receiving cirouits in connection with which my invention may be employed, and those which are shown are merely for illustrative purposes to indicate the possibilities of the uses to which my invention isadapted to be put.

Referring now in detail to the drawing: 1 designates a tubular member of suitable insulating material, such as fiber, upon which arewound the-primary and secondary coils 2 and 3 of an oscillatory transformer. Preferably the wire of the coil 2 is composed of a plurality of strands of fine wire. I-have' secured the best results by i the use of a wire composed of thirty-two strands of No. 38 wire. The secondary coil 3 consists of a single wire.

One terminal 4: of the coil 2 is adapted tobe connected to an antenna while the opposite terminal 5 thereof is adapted to be grounded. The terminals 6 and 7 of the. secondary coil 3 are adapted to. be connected in the grid circuit of the circuit sys- 9 tom of radio receiving apparatus.

Associated and electrically coupled with the secondar coil 3 is a rotor coil 10 which. is supporte upon a short tubular member 11 of suitable insulating material, such 1 the shafts 12 and 13 which are in alinement with each other. The wire which c.onstitutes the coil 10 preferably comprises a I have obtained the best results by the employment of a wire containing twenty strands of No. 38 wire. However, the employment of a plurality of employment of coils respectively consisting a of single wires of proper dimensions.

The terminals 11- and 15 at the opposite ends of the coil 10 are connected respectively to the shafts 12 and 13 and are secured thereon by means of clamping nuts 16 and 17. The shafts 12 and 13 extend through openings 20 through the tubular member 1 and, are situated in diametrically opposed relation toeach other, as shown. The outer end portions of the shafts extend through openings 21 in the outer or free ends of plate springs 22 and 23, which. .springs are situated. upon opposite sides of the member 1 and are fixedly secured thereto by means of screw bolts 24: and clamping nuts 25, as shown. Binding'nuts 26 ,are also provided upon the outer ends of the bolts 2% for the purpose of connecting therewith the ends of the wires of a circuit in which the coil 10 may be included.

The outer free end of the spring 22 bears and presses against a washer 28 which is held upon the shaft 12 by means of a nut 30 having engagement with a reduced screw threaded end portion 31 of the said shaft. The outer free end of the spring 23 bears and presses outwardly against the inner side of a sleeve 32 secured upon the shaft 13 by means of a binding screw 33. It will be noted that theisprings 22 and 23 operate with pulling forces tending to pull the shafts 12 and 13 outwardly or away from the axes of the members 1 and 11. B adjusting the springs 22 and 23 the position of the rotor member 11 and the coil 10 thereon with respect to the member 1 and consequently with respect to the coil 3 may be controlled and may thereby be positioned symmetrically with respect thereto.

In Fig. 41- of the drawing I have illustrated a circuit system indicating one manner or way in which the various coils previously referred to may be included. In said F ig, d 40 designates a grounded antenna which is connected to the primary coil 2. The sec- 52 ondary coil 3 is included in the tuned grid circuit which also includes a variable condenser 41, a grid resistance 42 and may also include a shunted variable capacity 43 as shown. The rotor coil 16 is included in the plate circuit 44 with the battery 45 and the telephone receivers 46. In Fig. 5 of the drawing I have shown the tuned grid circuit, comprising the parts 41, 42 and 43, as including the primary coil 2 to which the grounded antenna 40 is connected. The secondary coil and the rotor coil 10 are omitted.

In Fig. 6 of the drawing the grounded antenna 40 is connected to the primary coil 2 while the rotor coil 10 is connected in series with the secondary coil 3, thus forming a variometer. These coils are included in the grid circuit and are in series with the grid. This circuit also includes, as in the previous figures, the variable capacities dland 43 and also the shunted grid resistance'42.

In both Figs. 5 and 6 the plate circuit is of usual known construction.

The connections as indicated in these Figs. 4, 5 and 6 are merely indicative of the many other connections which may be effected by means of the unitary device illustrated in Figs. 1 to 3 of the drawing.

It will be seen that by my invention I have provided a structure by the employment of which the making of the connections in the circuit in various desired ways is greatly facilitated.

- I have discovered by actual and practical use that when a device embodying my invention is employed in the receiving system theefiiciency of the system is greatly enhanced and also that the reception of long distance Hertzian waves is greatly improved.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

In a radio receiving apparatus, a hollow supporting member having diametrically alined apertures therein, an inductance 0011 on said support, a rotor having an inductance coil, thereon, stub shafts passing through the apertures and supporting said rotor, spring bearing plates for said stub shafts carried by said supporting member, thrust members on said stub shafts to limit the endwise movement of said shafts and rotor, and means for adjusting the distance 

